|The Slip Control Boost system replaces traditional boosters, master cylinders and vacuum pumps.|
TRW Automotive Holdings, through its subsidiaries, is developing advanced regenerative braking technologies that integrate the enhanced safety of electronic stability control systems for hybrid vehicle and similar architectures.
The Company is developing two systems—Slip Control Boost (SCB) and Active Hydraulic Boost (AHB)—which offer full braking functionality for hybrids while incorporating high performance Electronic Stability Control and brake actuation within a 12-volt system architecture.
The systems can cover a range of vehicles from small passenger cars to SUVs.
Slip Control Boost offers a fully integrated stability and brake actuation system that replaces traditional boosters, master cylinders and vacuum pumps with an electro-hydraulic control unit (EHCU), and brake pedal simulator unit with a twin master cylinder to supply brake pressure.
This offers several advantages, according to TRW:
Ease of installation with fewer components to fit;
Improved packaging in the front dash area versus traditional vacuum boosters;
A decoupled brake pedal that is ideal for integration into autonomous or emergency braking systems; and
Best-in-class NVH (Noise Vibration Harshness) characteristics.
The SCB system is targeted for production in the 2007 calendar year.
The Active Hydraulic Braking system is compatible with any electronic stability control system and only replaces the brake actuation system with the EHCU, pedal simulator and master cylinder solution.
AHB offers the same advantages as the SCB system and provides a single slip control system trim across a full vehicle platform of conventional and hybrid vehicles. The AHB system is targeted for production in the 2009 calendar year.
Regenerative braking allows a vehicle to recapture and store part of the kinetic energy that would otherwise be lost to heat when braking. This energy is used to recharge the electric batteries and save on fuel in a hybrid architecture.
An electric motor can either use electricity to create torque, or reverse the process to use torque to create electricity. In regenerative braking, the torque created by the electric propulsion motors is applied to one or both of the axles to slow or stop the vehicle.
Because this regenerative force is not able to meet all the needs for braking over all speeds and conditions, conventional friction braking is also required and is blended with the motor torque to achieve full braking.
TRW is developing these advanced systems with the dual goals of providing a regenerative braking system that assists in boosting the power performance and fuel economy of hybrid vehicles while providing a braking system with excellent safety capabilities.
We are already in discussions with several global vehicle manufacturers who are expressing interest in these systems.—Josef Pickenhahn, vice president, Brake Engineering for TRW Automotive